President Barack Obama meets with President-elect Donald Trump in the Oval Office of the White House in Washington, Thursday, Nov. 10, 2016. (AP Photo/Pablo Martinez Monsivais)

WASHINGTON (MEDIA GENERAL) — President Barack Obama is a man bound by duty and tradition, and, today, carried out an expectation of his high office: welcoming a bitter rival turned successor into his home for a soft-focused sitdown.

President-elect Donald Trump and his wife Melania walked into the White House, welcomed by President and Mrs. Obama, to have a civil meeting and demonstrate the upcoming peaceful transfer of power.

Mr. Trump called the 90-minute meeting a “great honor.”

On such visits, the president and president-elect customarily exchange pleasantries and discuss business while the first lady shows the incoming first spouse around the family quarters and introduces her to the permanent residence staff.

Outside, city streets and social media might be filled with protests, but “Not My President” signs weren’t plastered along the West Wing corridors.

Despite the common dislike and distrust between outgoing and incoming administrations, they somehow manage to slap on a smile and carry out this essential task.

But behind the public smiles, the small presidential club is full of fraught relationships riddled with bruised egos, raw emotions and unlikely friendships.

Barack Obama and Donald Trump

Mr. Obama has spent the past several months traveling the country and enthusiastically highlighting Mr. Trump’s unreadiness for the job.

“He called Trump a ‘con artist and a know-nothing’ and said he was ‘temperamentally unfit to be commander in chief,'” reportsUSA Today. Mr. Trump retorted on Twitter, “Why is he campaigning instead of creating jobs & fixing Obamacare?”

The bad blood began flowing years ago as Mr. Trump stoked false rumors that Mr. Obama was not a natural born U.S. citizen and led the charge to unearth a birth certificate to prove as much.

At the White House Correspondents Dinner in 2011, Mr. Obama roasted Mr. Trump, then starring on NBC’s “Celebrity Apprentice,” for spreading conspiracies about his citizenship.

“He can finally get back to focusing on the issues that matter, like did we fake the moon landing, what really happened in Roswell, and where are Biggie and Tupac?” Mr. Obama said before a delighted crowd as Mr. Trump sat unamused.

Insiders have suggested that this public humiliation ultimately drove Mr. Trump to pursue the White House, viewing Mr. Obama handing him the keys to the executive mansion as the ultimate revenge.

The two men are now faced with mastering the dicey dance of transitioning from arch-enemies to respectful members of the world’s most elite club.

It’s been done before, with varying degrees of success.

Dwight Eisenhower and Harry Truman

Harry Truman was president while Dwight D. Eisenhower became a celebrated five-star general who helped lead America to victory over Nazi Germany in World War II.

“In a private meeting, Truman proposed that he and Eisenhower run together on the Democratic ticket,” following the war in 1948, “with Eisenhower as the presidential candidate and Truman in second position,” reports UVA’s Miller Center.

Eisenhower declined the invitation, and Truman won re-election at the top of the ticket.

Once 1952 rolled around and Eisenhower, a Republican, was running against Democratic Truman ally Adlai Stevenson, the Truman-Eisenhower relationship quickly soured.

“Truman sent an invitation to both Eisenhower and his opponent, Democratic nominee Adlai Stevenson, to be briefed on national security matters, then have lunch at the White House and attend a cabinet meeting,” but “only Stevenson accepted,” recounts the Christian Science Monitor.

On Inauguration Day in 1953, the men frostily greeted each other at the White House and Eisenhower rejected Truman’s offer to have coffee together.

For the next eight years, both men harbored resentments; there were no friendly visits, no olive branches extended.

Finally, “fences were later mended after Eisenhower left office, when Eisenhower visited Truman to ask for advice on how to design his private library,” writes the CS Monitor.

Richard Nixon and Lyndon Johnson

Presidents Johnson and Nixon were like “two scorpions in a bottle,” according to the book The Presidents Club.

And for good reason.

Nixon was notoriously devious and known to be politically ruthless. But behind the curtain, Johnson was a take-no-prisoners operator as well.

LBJ declined to run for re-election in 1968, due in large part to the widespread furor over the prolonged and bloody Vietnam War, with sounds of daily protests piercing the White House’s windows and disrupting the serene interior.

Johnson’s peace talks to end the war crumbled, and FBI wiretaps suggested that his nemesis Richard Nixon was behind their demise.

“By the time of the election in November 1968, LBJ had evidence Nixon had sabotaged the Vietnam war peace talks – or, as he put it, that Nixon was guilty of treason and had ‘blood on his hands,'” reports the BBC.

Nixon eventually won the presidency by a slim margin and expanded the war.

Needless to say, there was no love lost between the men; Johnson died in 1973 before seeing Nixon forced to resign in disgrace in 1974.

Jimmy Carter and Bill Clinton

Jimmy Carter claims the longest post-presidency in American history and is also the least popular among his peers, according to The Presidents Club.

The Georgian is gentle and genial in public but reportedly highly calculating in private, riling his successors by freelancing on the international stage in flagrant breaches of protocol.

Carter doesn’t play by the “if you don’t have anything nice to say” principle employed by other former POTUSes.

President Bill Clinton ran into one such incident during in 1994.

Clinton asked Carter to be part of a delegation charged with negotiating a peaceful resolution to civil and military unrest in Haiti, but displeased the White House by going off the grid for a period of time and pressing his own views instead of the government’s official position.

And this wasn’t their first run-in.

The two southern governors went way back, with Clinton blaming Carter for sending Cuban refugees, including criminals and the mentally ill, to be held in Arkansas in 1980 despite public outcry.

Chaos commenced at the Cuban refugee holding facility in short order.

“Plumes of smoke billowed high into the illuminated night sky from barracks that had been set afire,” reported the Washington Post. “Shotgun-toting civilians in pickup trucks loomed a mile or so beyond the gate. The mood was tense and chaotic.”

Clinton lost his re-election bid and always blamed Carter for overriding his strong objections to the refugee placement program.

Bill Clinton and George H.W. Bush

In 1992, Clinton was elected president and ousted one-term President George H.W. Bush from the Oval Office.

Mr. Bush’s loss was a crushing defeat for a man who just a few months prior was riding high in the polls, thanks to the swift success of an American-led coalition in the first Gulf War.

“Clinton defeated Bush Sr. in 1992 after portraying him as feeble and out of touch. Bush Jr. still describes that loss as one of the most painful moments of his and his father’s lives,” Real Clear Politics writes.

Clinton and the elder Bush have “become really great friends; in fact almost like family and that’s like a jealousy for the rest of the Bush kids,” family intimate Andy Card told CNN. “They think they got this other brother named Bill Clinton. It is a wonderful warm relationship.”

It just goes to show that anything is possible when it comes to politics and the complex interpersonal dynamics of presidents and their predecessors.

On the Trump-Obama front, forced smiles and a firm handshake will have to suffice for now.